Casgliadau Arlein
Amgueddfa Cymru
Chwilio Uwch
Slate
Appears to be a stock slates (crawan gownt), which has been used for figures and calculations, from Rhiwfachno Quarry, Cwm Penmachno. Carefully lined and bears a mass of figures and calculations, with some equations.
Nid yw sylwadau ar gael ar hyn o bryd. Ymddiheuriadau am yr anghyfleustra.